CVE-2026-20215: ClamAV out-of-bounds write in 7z file format parser

CVE-2026-20215 · Severity: high · CVSS 7.5 · Published 2026-07-01

A vulnerability in the ClamAV antivirus engine, which is used to scan files for threats, could allow an attacker to crash the scanning service. By sending a specially crafted 7z compressed file, an attacker can cause the security software to stop functioning, potentially leaving the system unprotected or requiring a manual reboot. On Windows systems, this is particularly impactful as the scanning process runs with high privileges, which could lead to broader system instability.

Technologies: Cisco ClamAV, Cisco Secure Endpoint Connector for Linux, Cisco Secure Endpoint Connector for Mac, Cisco Secure Endpoint Connector for Windows. Vendors: Cisco.

Quick answers

Is CVE-2026-20215 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-20215 being exploited in the wild.
How severe is CVE-2026-20215?
High severity, with a CVSS score of 7.5, published 1 July 2026.
Which products and versions are affected?
Cisco Secure Endpoint Connector for Linux Prior to 1.29.0; Cisco Secure Endpoint Connector for Mac Prior to 1.27.2; Cisco Secure Endpoint Connector for Windows Prior to 8.6.2.
Is there a fix for CVE-2026-20215?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-20215 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-20215?
Check whether you run Cisco ClamAV, Cisco Secure Endpoint Connector for Linux, Cisco Secure Endpoint Connector for Mac or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

This vulnerability exists in the 7z file format parser of ClamAV due to improper boundary checks during the scanning of 7z content. An unauthenticated, remote attacker can exploit this by submitting a crafted 7z file, leading to an out-of-bounds buffer write. While the primary impact is the termination of the ClamAV scanning process (Denial of Service), memory corruption could potentially lead to other expanded impacts. On Windows-based Cisco Secure Endpoint Connectors, the process runs in a privileged context, making the impact more severe compared to Linux or Mac implementations. Cisco has released updates for affected Secure Endpoint products to address this issue.

Affected products

  • Cisco ClamAV
  • Cisco Secure Endpoint Connector for Windows Prior to 8.6.2
  • Cisco Secure Endpoint Connector for Linux Prior to 1.29.0
  • Cisco Secure Endpoint Connector for Mac Prior to 1.27.2

Timeline

  • 2026-07-01: advisory: Cisco published the security advisory.

References

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